Special Containment Procedures:
SCP-XXXX is to be kept in a 4 x 3 x 3m ventilated and soundproof humanoid containment chamber, and is allowed to have the following items in its chamber:

An ash tray

Any brand of tobacco or cigarettes

SCP-XXXX is to be separated from SCP-XXXX-1 when not in testing. SCP-XXXX-1 is to be hung up in a wooden closet in Containment Unit 16 at Site-47.
Further testing with SCP-XXXX is to be approved by personnel with a clearance of level 3 or higher, as is cross-testing with other SCPs.
Should SCP-XXXX request to enter the cafeteria, this has to be approved by the current Security chief, and SCP-XXXX is to be under guards' supervision while in the cafeteria.

Description:
SCP-XXXX, as of █/█/2017, is a 31 year old African American male of average build, standing 1.7 meters tall. SCP-XXXX has the ability to make an "Illness Trade", which can exchange any number of subject's illnesses with each other.
Upon subject's consent, SCP-XXXX puts on a grey coloured vest, which has a pack of tobacco in one of the pockets. The vest will be referred to as SCP-XXXX-1.

SCP-XXXX will then roll a cigarette, and by standard trading procedure, SCP-XXXX and SCP-XXXX-2 smoke the entire cigarette in turns. Once the cigarette is finished, this renders the current trade "complete", having successfully exchanged each other's illness/disease.
Upon a complete trade, SCP-XXXX and SCP-XXXX-2 shake hands, and return to their previous activity. Testing shows that illnesses indeed exchange, SCP-XXXX-2 receiving one of SCP-XXXX-1's illnesses, and vice-versa. Test log reveals that some mental illnesses can be traded, but these are limited to their severity. (See Test Log XXXX-A).
The motivation behind these trades originate from a personal experience in SCP-XXXX's past.(See Interview XXXX-B).

For a more detailed retrieval log, refer to document SCP-XXXX-R1.
Undercover Agent █████, at the time of initial recovery of SCP-XXXX, was working for SCP-XXXX's local hospital, The [DATA EXPUNGED].
One specific male, later to become SCP-XXXX, made multiple appointments in a single month, sometimes in a single week. The subject received treatment for varying mental and physical illnesses, such as, but not limited to:

Fibromyalgia

Constipation

Lung infection

Various types of cancer

Agent █████ contacted a nearby MTF unit, and SCP-XXXX has been successfully contained.

In the event that SCP-3836 trades with SCP-XXXX-2, and SCP-XXXX-2 has a lethal disease/illness, SCP-XXXX will show less symptoms of this disease/illness compared to SCP-XXXX-2. Research and interviews on this phenomenon are still ongoing and are closely monitored by Dr. ██████.

It should also be mentioned that SCP-XXXX-1 is required for a trade, as are all of its contents, and
SCP-XXXX-1 will not work without SCP-XXXX.

Note from Researcher ██████: We should put this man in the medical bay, and have him take care of our personnel. Think of how useful he would make himself! Trading diseases for minor colds, and then taking a pill of SCP-500 to get rid of them all! This will be beneficial to us I tell you!

Note from O5-Command: Absolutely not! We can understand why you would think that this is a good idea, but there's no infinite supply of SCP-500, nor do we know if SCP-XXXX will co-operate with this idea at all. Not only that, but it's inhumane. The foundation is cold, not cruel. Putting a fully sapient man in the medical bay to serve as a major disease disposal? No, end of discussion.

Subjects: Subject D-11734, SCP-XXXX and SCP-XXXX-1
D-11734 is a caucasian male of average build and height, and has been diagnosed with severe depression. SCP-XXXX has been injected with a viral infection of the upper respiratory tract. This disease is less severe, and this test log is to determine if SCP-XXXX can exchange this minor viral infection for a more severe mental illness.

D-11734 is introduced to SCP-XXXX.

SCP-XXXX is sitting on a chair, and SCP-XXXX-1 is hanging on the chair.

Dr.████ informs D-11734 of SCP-XXXX, and D-11734 approaches SCP-XXXX

<Begin Log of interaction between SCP-XXXX and D-11734, 11:02:45 AM>

SCP-XXXX: Oh, D-Class. What do you want?

D-11734: Hey, You're the trader guy, right?

SCP-XXXX: Indeed I am. Why, were you looking to trade with me? I've got a nasty cold right now. What's bugging you?

D-11734: I've been diagnosed with severe depression about a week ago. Listen, I'm willing to trade it in for a cold!

SCP-XXXX: My common cold, in exchange for your severe depression…I think I can make it work. You ready?

D-11734: Ready.

SCP-XXXX is seen putting on SCP-XXXX-1, and rolls a cigarette with the contents of SCP-XXXX-1.

SCP-XXXX then hands the cigarette to D-11734, and provides a lighter.

SCP-XXXX: Alright, now you just smoke that untill it's about halfway done, then I'll smoke the rest of it, which should complete the trade.

D-11734: Fair enough.

D-11734 smokes on the cigarette, and has a small, undocumented conversation with SCP-XXXX.

SCP-XXXX then takes the cigarette, smokes it untill it's completely done, and is seen to be thinking.

SCP-XXXX sit back on his chair, and stares at the ground for serveral minutes.

SCP-XXXX: D-Class, I've given you my cold, but I could not fully exchange your depression for my cold. Your depression should be less severe, although you should feel better than before.

D-11734: It's better than nothing I guess.

SCP-XXXX and D-11734 shake hands, and both are returned to their respective chambers.

<End Log>

Analysis: SCP-XXXX is not able to fully exchange diseases/illnesses when the diffrence in severity is too high. SCP-XXXX has been in therapy sessions since this test, and has shown signs of mental stability. Object returned to containment.

Dr. █████: Good afternoon SCP-XXXX, I am Dr.█████. How are you feeling today?

SCP-XXXX: I feel like I'm in prison…

Dr. █████: This basically is a prison, but we've contained you for….studying. How may I adress you, aside from your designation?

SCP-XXXX: You may call me Jack.

Dr. █████: Okay, Jack, I've got some questions for you, are you willing to co-operate with me and answer these questions?

SCP-XXXX: Sure, why not.

Dr. █████: Okay, let's start with your uh, "Trading". How did you find out about this ability?

SCP-XXXX: I still remember it very well, I was about, 13 or, 14. My father had been diagnosed with Stage-3 lung cancer. I was devastated. In the period where he was in hospital, I sometimes said that I would be willing to trade his cancer for my stomach aches, my running noses. Anything. And then it happened. Out of nowhere, I put on a gray vest, and I roll a cigarette. It was like, I knew exactly what to do. Well, by now I think you know what happened..

Dr. █████: My guess is that, you initiated your first trade?

SCP-XXXX: Damn right. My father is still alive to this day, all thanks to me. After my first trade, I felt the need to help more people out. I felt like I had a duty.

Dr. █████: I see. Say, Jack, how come you're still alive too? You've been trading your cold with cancer, your anxiety with [DATA EXPUNGED]. How did you survive all of that?

SCP-XXXX: Doc, I'd be happy to know how. I wish I could teach others to perform this trick. It'd do so much good to the world.

Dr. █████: Jack, we've contained you to study you. I ask this of you: Your full co-operation in future testing, studies, interviews, and anything else related to you and your ability.

Dr. █████: You will be provided with basic human needs, means of entertainment, and you may request other items in your chamber. They have to be approved by O5, however.

SCP-XXXX: Doc, I'll fucking volunteer. Let's get right to it.

Dr. █████: Seems like a good plan.

<End Log>

Closing Statement: SCP-XXXX seems to have good intent. Further testing on diffrent SCP's will be requested by Dr.█████.